1. Field of the Invention
The invention relates to a photoelectric switch, and more particularly to a photoelectric switch that uses an angular change to control a switch status and a photoelectric switch housing thereof.
2. Description of the Related Art
Referring to FIG. 1, a conventional photoelectric switch 1 is shown to include a case 11 and a cover 12 coupled to each other, a light emitter 13 and a light receiver 14 mounted oppositely in the case 11, and a ball 15. The case 11 has a tubular wall 111 surrounding an X-axis and defining a rolling chamber 110, and two notches 112 formed in the tubular wall 111 and respectively corresponding in position to the light emitter 13 and the light receiver 14. Light emitted by the light emitter 13 is received by the light receiver 14 through the notches 112. The ball 15 is disposed in the rolling chamber 110.
Through this configuration, in the presence of an external force, the ball 15 is rollable between a non-blocking position that unblocks a light passage to place the switch 1 in an “ON” state, and a blocking position that blocks the light passage to shift the switch 1 to an “OFF” state. Hence, the ON/OFF control of the switch device 1 can be achieved.
Although the conventional photoelectric switch 1 uses the recesses 112 to restrict a light transmission range of the light emitter 13, since each recess 112 has one open end, scattering of light toward the cover 12 cannot be effectively restricted. Further, since a seam between the case 11 and the cover 12 is also within a scattering area of the light, not only will the communication be adversely affected by refraction of the scattered light, but also leaking of the light is likely to happen. Hence, the photoelectric switch 1 is prone to malfunction.
Referring to FIG. 2, a conventional rolling-ball switch, as disclosed by the applicant in Taiwanese Patent No. I310952, mainly includes a base 21 and a cover body 22 coupled to each other, a light emitter 23 and a light receiver 24 mounted oppositely within the base 21 and the cover body 22, an inner tubular wall 26 and an inner cover 27 disposed between the light emitter 23 and the light receiver 24 and defining a light passage 25, and a ball 28 disposed in a space defined by the inner tubular wall 26 and the inner cover 27. Through this configuration, light can only travel along the light passage 25. Hence, the ON/OFF control of the switch can be achieved.
Although the aforesaid rolling-ball switch can achieve the purpose of restricting a light transmission range and light leakage, because of the additional two components, that is, the inner tubular wall 26 and the inner cover 27, assembling procedures and costs of the aforesaid conventional rolling-ball switch are increased.